Human embryonic stem (ES) cells are pluripotent cells isolated from developing blastocysts. ES cell culture requires feeder cells to support their growth, self renewal and maintenance of pluripotency. The most commonly used feeder cells in human ES cell culture are fibroblasts isolated from 13.5 days mouse embryos (MEF). One of the major goals of human ES cell research is to use differentiated derivatives of ES cells for cell therapies for diseases like Parkinson's. Use of feeder cells of nonhuman origin is a major hindrance for both diagnostic and clinical applications because of potential zoonotic transmission. Another challenge to neural stem cell therapies is generating pure populations of the cell type of interest. Undesired cell types, such as left over ES cells, may produce clinical complications. These adherent neuronal progenitors are more uniform than NP cell grown as neurospheres. However, that method still requires the use of MEF to derive the adherent progenitor cells. In the present report, we demonstrate for the first time that adherent NP cells can be derived from human ES cells without the use of feeder cells.
Embryonic stem (ES) cells serve as an excellent in vitro system for studying differentiation events and for developing methods of generating various specialized cells for future regenerative therapeutic applications.
The understanding of mammalian cellular differentiation and cell fate specification are progressing intensively using an in vitro system, comprised of embryonic stem cells. Research on the cell fate specification in the central nervous system is of enormous interest given the therapeutic potential in neuronal repair strategies.
Human ES Cell differentiation to neural cell stem cells have broad applications from potential cell therapies for anyone of 500 neurodegenerative diseases to use in drug discovery and toxicity assays for neurological applications. Already mouse ES cell studies have had promising results in transplant models as shown by their demonstration of efficacy in a rat model of Parkinson's Disease.
In addition, primate ES cells can play an important intermediate translational role as stem cell differentiation strategies are transitioned from rodent systems to human clinical applications. Clinical trials for human ES cells as a therapy will be greatly enhanced by data gathered in a primate transplant model. Primate and human ES cells share many characteristics, making primate ES cells an appropriate model in which to refine differentiation protocols for translational studies.
In order for neural progenitors to be used in clinical applications, their method of derivation must be scalable and free from contaminating cell types.